The program theme is to identify effective breast cancer screening strategies for women with diverse levels of breast cancer risk to maximize screening benefits while minimizing potential harms. Program aims follow the premise that breast cancer screening will be most effective when: guidelines are based on accurate risk estimates that are tied to the effectiveness and harms of screening tests;women and physicians are informed about screening test performance based on risk level;risk-based screening practices are equitable;and high-quality comparative effectiveness research results are disseminated into community practice. Program goals will be met through three complementary research projects and three shared resource cores. Project 1, Risk Assessment in Community Practice: Developing Better Models, will improve prediction of breast cancer and breast cancer subtypes among women of varying ages and race/ethnicity and evaluate whether predicted risk can be used to optimize screening outcomes. Project 2, Comparative Effectiveness of Imaging Strategies for Breast Cancer Screening in Community Practice, will characterize the performance of advanced imaging technologies and screening strategies according to age, race/ethnicity, breast density, and overall breast cancer risk. Project 3, Community-based Utilization of Breast Imaging Technologies, will assess risk-based screening in diverse populations and identify disparities in access and use of new technologies. The Administrative Core will support logistical requirements and facilitate communication and data sharing. The Biostatistics and Data Management Core will coordinate data collection, management, and analysis and will develop statistical methods. The Comparative Effectiveness Core will use simulation modeling to estimate long-term implications of different screening practices on population health. The program represents an integrated effort to improve screening with the overall aim of averting deaths from breast cancer while minimizing harms.